I launch my application in cmd. I compiled it by Cmake without WIN32_EXECUTABLE, so it hangs in cmd (i.e. is launched as not detached). Now I want to close the console and try to achieve this by calling FreeConsole().
This works in case I double-click the application -- the black console is flashes quickly and gets closed. But it does not work when I launch it in cmd. The cmd is still attached to the launched application and FreeConsole() does not help.
Is there any way to detach it from cmd programmatically? I have found the opportunity to run start /b myapp, but I would like to do it in a programmatical way.
UPDATE
A rough implementation of the answer of Anders for those who are interested -- see below. In this implementation I pass all the arguments, supplied to main.com, to the child process main.exe.
// main.cpp
// cl main.cpp
// link main.obj /SUBSYSTEM:WINDOWS /ENTRY:"mainCRTStartup"
//
#include <stdio.h>
#include <Windows.h>
int main(int argc, char** argv)
{
if (AttachConsole(ATTACH_PARENT_PROCESS)) {
freopen("CONOUT$", "w", stdout);
freopen("CONOUT$", "w", stderr);
freopen("CONIN$", "r", stdin);
}
for (int i = 0; i < argc; i++)
printf("--%s", argv[i]);
printf("Hello\n");
int k = 0;
scanf("%d", &k);
printf("%d\n", k);
return 0;
}
// helper.cpp
// cl helper.cpp
// link helper.obj /OUT:main.com
//
#include <windows.h>
#include <stdio.h>
#include <string.h>
void main( int argc, char **argv )
{
STARTUPINFO si;
PROCESS_INFORMATION pi;
ZeroMemory( &si, sizeof(si) );
si.cb = sizeof(si);
ZeroMemory( &pi, sizeof(pi) );
// Reconstructing the command line args for main.exe:
char cmdLine[32767] = { 0 };
strcpy(cmdLine, "main.exe ");
int shift = strlen("main.exe ");
for (int i = 1 ; i < argc; i++)
{
strcpy(cmdLine + shift, argv[i]);
const int argLength = strlen(argv[i]);
cmdLine[shift + argLength] = ' ';
shift += (argLength + 1);
}
printf("\n!!!!%s!!!!!%s\n", cmdLine, GetCommandLine());
// Start the child process.
// https://learn.microsoft.com/en-us/windows/win32/procthread/creating-processes
//
if( !CreateProcess(NULL, // No module name (use command line)
cmdLine, // Command line
NULL, // Process handle not inheritable
NULL, // Thread handle not inheritable
FALSE, // Set handle inheritance to FALSE
0, // No creation flags
NULL, // Use parent's environment block
NULL, // Use parent's starting directory
&si, // Pointer to STARTUPINFO structure
&pi ) // Pointer to PROCESS_INFORMATION structure
)
{
printf( "CreateProcess failed (%d).\n", GetLastError() );
return;
}
// Wait until child process exits.
WaitForSingleObject( pi.hProcess, INFINITE );
// Close process and thread handles.
CloseHandle( pi.hProcess );
CloseHandle( pi.hThread );
}
